prests rpests persts eprsts repsts erpsts prsets rpsets psrets sprets rspets srpets pesrts epsrts pserts sperts esprts seprts respts erspts rsepts srepts esrpts serpts pretss rpetss pertss eprtss reptss erptss prtess rptess ptress tpress rtpess trpess petrss eptrss pterss tperss etprss teprss retpss ertpss rtepss trepss etrpss terpss prstes rpstes psrtes sprtes rsptes srptes prtses rptses ptrses tprses rtpses trpses pstres sptres ptsres tpsres stpres tspres rstpes srtpes rtspes trspes strpes tsrpes pestrs epstrs psetrs spetrs esptrs septrs petsrs eptsrs ptesrs tpesrs etpsrs tepsrs psters spters ptsers tpsers stpers tspers estprs setprs etsprs tesprs steprs tseprs restps erstps rsetps sretps esrtps sertps retsps ertsps rtesps tresps etrsps tersps rsteps srteps rtseps trseps streps tsreps estrps setrps etsrps tesrps sterps tserps presst rpesst persst eprsst repsst erpsst prsest rpsest psrest sprest rspest srpest pesrst epsrst pserst sperst esprst seprst respst erspst rsepst srepst esrpst serpst presst rpesst persst eprsst repsst erpsst prsest rpsest psrest sprest rspest srpest pesrst epsrst pserst sperst esprst seprst respst erspst rsepst srepst esrpst serpst prsset rpsset psrset sprset rspset srpset prsset rpsset psrset sprset rspset srpset pssret spsret pssret spsret sspret sspret rsspet srspet rsspet srspet ssrpet ssrpet pessrt epssrt psesrt spesrt espsrt sepsrt pessrt epssrt psesrt spesrt espsrt sepsrt pssert spsert pssert spsert sspert sspert essprt sesprt essprt sesprt sseprt sseprt resspt ersspt rsespt srespt esrspt serspt resspt ersspt rsespt srespt esrspt serspt rssept srsept rssept srsept ssrept ssrept essrpt sesrpt essrpt sesrpt sserpt sserpt pretss rpetss pertss eprtss reptss erptss prtess rptess ptress tpress rtpess trpess petrss eptrss pterss tperss etprss teprss retpss ertpss rtepss trepss etrpss terpss prests rpests persts eprsts repsts erpsts prsets rpsets psrets sprets rspets srpets pesrts epsrts pserts sperts esprts seprts respts erspts rsepts srepts esrpts serpts prtses rptses ptrses tprses rtpses trpses prstes rpstes psrtes sprtes rsptes srptes ptsres tpsres pstres sptres tspres stpres rtspes trspes rstpes srtpes tsrpes strpes petsrs eptsrs ptesrs tpesrs etpsrs tepsrs pestrs epstrs psetrs spetrs esptrs septrs ptsers tpsers psters spters tspers stpers etsprs tesprs estprs setprs tseprs steprs retsps ertsps rtesps tresps etrsps tersps restps erstps rsetps sretps esrtps sertps rtseps trseps rsteps srteps tsreps streps etsrps tesrps estrps setrps tserps sterps prstse rpstse psrtse sprtse rsptse srptse prtsse rptsse ptrsse tprsse rtpsse trpsse pstrse sptrse ptsrse tpsrse stprse tsprse rstpse srtpse rtspse trspse strpse tsrpse prsste rpsste psrste sprste rspste srpste prsste rpsste psrste sprste rspste srpste pssrte spsrte pssrte spsrte ssprte ssprte rsspte srspte rsspte srspte ssrpte ssrpte prtsse rptsse ptrsse tprsse rtpsse trpsse prstse rpstse psrtse sprtse rsptse srptse ptsrse tpsrse pstrse sptrse tsprse stprse rtspse trspse rstpse srtpse tsrpse strpse pstsre sptsre ptssre tpssre stpsre tspsre psstre spstre psstre spstre ssptre ssptre ptssre tpssre pstsre sptsre tspsre stpsre stspre tsspre sstpre sstpre tsspre stspre rstspe srtspe rtsspe trsspe strspe tsrspe rsstpe srstpe rsstpe srstpe ssrtpe ssrtpe rtsspe trsspe rstspe srtspe tsrspe strspe stsrpe tssrpe sstrpe sstrpe tssrpe stsrpe pestsr epstsr psetsr spetsr esptsr septsr petssr eptssr ptessr tpessr etpssr tepssr pstesr sptesr ptsesr tpsesr stpesr tspesr estpsr setpsr etspsr tespsr stepsr tsepsr pesstr epsstr psestr spestr espstr sepstr pesstr epsstr psestr spestr espstr sepstr pssetr spsetr pssetr spsetr sspetr sspetr essptr sesptr essptr sesptr sseptr sseptr petssr eptssr ptessr tpessr etpssr tepssr pestsr epstsr psetsr spetsr esptsr septsr ptsesr tpsesr pstesr sptesr tspesr stpesr etspsr tespsr estpsr setpsr tsepsr stepsr pstser sptser ptsser tpsser stpser tspser psster spster psster spster sspter sspter ptsser tpsser pstser sptser tspser stpser stsper tssper sstper sstper tssper stsper estspr setspr etsspr tesspr stespr tsespr esstpr sestpr esstpr sestpr ssetpr ssetpr etsspr tesspr estspr setspr tsespr stespr stsepr tssepr sstepr sstepr tssepr stsepr restsp erstsp rsetsp sretsp esrtsp sertsp retssp ertssp rtessp tressp etrssp terssp rstesp srtesp rtsesp trsesp stresp tsresp estrsp setrsp etsrsp tesrsp stersp tsersp resstp ersstp rsestp srestp esrstp serstp resstp ersstp rsestp srestp esrstp serstp rssetp srsetp rssetp srsetp ssretp ssretp essrtp sesrtp essrtp sesrtp ssertp ssertp retssp ertssp rtessp tressp etrssp terssp restsp erstsp rsetsp sretsp esrtsp sertsp rtsesp trsesp rstesp srtesp tsresp stresp etsrsp tesrsp estrsp setrsp tsersp stersp rstsep srtsep rtssep trssep strsep tsrsep rsstep srstep rsstep srstep ssrtep ssrtep rtssep trssep rstsep srtsep tsrsep strsep stsrep tssrep sstrep sstrep tssrep stsrep estsrp setsrp etssrp tessrp stesrp tsesrp esstrp sestrp esstrp sestrp ssetrp ssetrp etssrp tessrp estsrp setsrp tsesrp stesrp stserp tsserp ssterp ssterp tsserp stserp
Note: these 'words' (valid or invalid) are all the permutations of the word prests. These words are obtained by scrambling the letters in prests.